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(Article of periodic en Anglais - 2014)

Document title

Geophysical constraints on deep weathering and water storage potential in the Southern Sierra Critical Zone Observatory

Authors(s) and Affiliation(s)

HOLBROOK W.S. (1) ; RIEBE C.S. (1) ; ELWASEIF M. (1) ; HAYES J.L. (1) ; BASLER-REEDER K. (2) ; HARRY D.L. (2) ; MALAZIAN A. (3) ; DOSSETO A. (4) ; HARTSOUGH P.C. (3) ; HOPMANS J.W. (3) ;
(1) Dept. of Geology and Geophysics, Univ. of Wyoming, Laramie, ETATS-UNIS
(2) Dept. of Geosciences, Warner College of Natural Resources, Colorado State Univ., Fort Collins, ETATS-UNIS
(3) Dept. of Land, Air and Water Resources, Univ. of California, Davis, ETATS-UNIS
(4) Wollogong Isotope Geochronology Lab., School of Earth and Environmental Sciences, Univ., Wollongong, AUSTRALIE

Abstract

Here the AA. use seismic refraction and resistivity imaging techniques to estimate variations in regolith thickness and porosity across a forested slope and swampy meadow in the Southern Sierra Critical Zone Observatory (SSCZO). The inferred weathering zone consists of roughly equal thicknesses of saprolite and moderately weathered bedrock. A minimum-porosity model assuming dry pore space shows porosities as high as 50% near the surface, decreasing to near zero at the base of weathered rock. Physical properties of saprolite samples from hand augering and push cores are consistent with the rock physics model when variations in pore saturation are taken into account. The results indicate that saprolite is a crucial reservoir of water. When coupled with published erosion rates from cosmogenic nuclides, the geophysical estimates of weathering zone thickness imply regolith residence times on the order of 10 000 years. Thus, soils at the surface today may integrate weathering over glacial–interglacial fluctuations in climate

Source

Article of periodic

published at : Earth surface processes and landforms / ISSN 0197-9337 / CODEN ESPLDB

Editor : Wiley, Chichester - ROYAUME-UNI (1981)

Millesime : 2014, vol. 39, no3 [pp. 366-380]

Bibliographic references : 2 p.

Collation : 11 fig., 1 tabl.

Language

Anglais

INIST-CNRS, Cote INIST : 17355

Digital Object Identifier

Go to electronic document thanks to its DOI : doi:10.1002/esp.3502

Tous droits réservés © Prodig - Bibliographie Géographique Internationale (BGI), 2014
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